php怎样分页来显示mysql数据库中的一条数据的内容,即每页显示这条数据的几个字符,给一段代码范例好吗O(∩_∩)O谢谢!假使我的数据库叫做xinxi,字段有id,all,all是内容,需要显示的对象,字段类型式'text',3000个字节。我在前台如果需要每页显示1200个字节,分页来显示这了数据的内容,怎样写啊?程序是php。
1. 截取GB2312中文字符串<?php//截取中文字符串function mysubstr($str, $start, $len) { $tmpstr = ""; $strlen = $start + $len; for($i = 0; $i < $strlen; $i++) { if(ord(substr($str, $i, 1)) > 0xa0) { $tmpstr .= substr($str, $i, 2); $i++; } else $tmpstr .= substr($str, $i, 1); } return $tmpstr;}?>2. 截取utf8编码的多字节字符串<?php//截取utf8字符串function utf8Substr($str, $from, $len){ return preg_replace('#^(?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,'.$from.'}'. '((?:[\x00-\x7F]|[\xC0-\xFF][\x80-\xBF]+){0,'.$len.'}).*#s', '$1',$str);}?>3. UTF-8、GB2312都支持的汉字截取函数<?php/*Utf-8、gb2312都支持的汉字截取函数cut_str(字符串, 截取长度, 开始长度, 编码);编码默认为 utf-8开始长度默认为 0*/ function cut_str($string, $sublen, $start = 0, $code = 'UTF-8'){ if($code == 'UTF-8') { $pa = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|\xe0[\xa0-\xbf][\x80-\xbf]|[\xe1-\xef][\x80-\xbf][\x80-\xbf]|\xf0[\x90-\xbf][\x80-\xbf][\x80-\xbf]|[\xf1-\xf7][\x80-\xbf][\x80-\xbf][\x80-\xbf]/"; preg_match_all($pa, $string, $t_string); if(count($t_string[0]) - $start > $sublen) return join('', array_slice($t_string[0], $start, $sublen))."..."; return join('', array_slice($t_string[0], $start, $sublen)); } else { $start = $start*2; $sublen = $sublen*2; $strlen = strlen($string); $tmpstr = ''; for($i=0; $i<$strlen; $i++) { if($i>=$start && $i<($start+$sublen)) { if(ord(substr($string, $i, 1))>129) { $tmpstr.= substr($string, $i, 2); } else { $tmpstr.= substr($string, $i, 1); } } if(ord(substr($string, $i, 1))>129) $i++; } if(strlen($tmpstr)<$strlen ) $tmpstr.= "..."; return $tmpstr; }} $str = "abcd需要截取的字符串";echo cut_str($str, 8, 0, 'gb2312');?>4. BugFree 的字符截取函数<?php/** * @package BugFree * @version $Id: FunctionsMain.inc.php,v 1.32 2005/09/24 11:38:37 wwccss Exp $ * * * Return part of a string(Enhance the function substr()) * * @author Chunsheng Wang <wwccss@263.net> * @param string $String the string to cut. * @param int $Length the length of returned string. * @param booble $Append whether append "...": false|true * @return string the cutted string. */function sysSubStr($String,$Length,$Append = false){ if (strlen($String) <= $Length ) { return $String; } else { $I = 0; while ($I < $Length) { $StringTMP = substr($String,$I,1); if ( ord($StringTMP) >=224 ) { $StringTMP = substr($String,$I,3); $I = $I + 3; } elseif( ord($StringTMP) >=192 ) { $StringTMP = substr($String,$I,2); $I = $I + 2; } else { $I = $I + 1; } $StringLast[] = $StringTMP; } $StringLast = implode("",$StringLast); if($Append) { $StringLast .= "..."; } return $StringLast; }} $String = "CodeBit.cn -- 简单、精彩、通用";$Length = "18";$Append = false;echo sysSubStr($String,$Length,$Append);?>